python文件操作方法

f1 = open('E:/111.txt','r',buffering=4096)
f2 = open('E:/222.txt','r',buffering=4096)
list = f1.readlines()
print(list)
list1 = f2.readlines()
for i in list:
    li = re.split(' ',i)
    li = re.sub('\n','',i)
    print(li[1])
    z = zip(li[0])
print(list)
    s = set(list1)
print(s)
    s_len = len(s)
    for i1 in li:
        print(i)
    i_len = len(i)
    k_len = len(k)
    s1 = s.add(i)
    s2 = s.add(k)
    print(s1)
    if
    # print(i_len)
    s = s.add(i)
    print(s)
    print(s)
    if (len(s)-i_len==i_len):
        print(i)
    else:
        pass



for file in f1.readlines():
    print(file)
    ref = file
    print(ref)

for i in f2.readlines():
    k = re.findall('','')
    a = re.split(' ',i)
    print(ref)
        for l in a:
f = open('a.txt','rb')#必须以二进制读
f.seek(3,1)#第二个参数相对位置
f.seek(-3,2)#第二个参数倒数光标
读取文件最后一行的日志：方法

f1 = open('a.txt','rb')
# li = f1.readlines()
for i in f1:
    offset = -5
    while 1:
        f1.seek(offset,2)#移动光标到最后倒着读
        f = f1.readlines()
        if len(f) > 1:
            print('文件最后一行是%s'%(f[-1].decode('utf8')))
            break
        else:
            offset*=2